Video Transcript:

GLORIA PENNER (Host): Violence against police south of the border took another deadly turn this week. Three offers were killed and one was injured in attacks linked to drug cartels.  Here to tell us more is Amy Isackson who covers the border for KPBS news, also joined by Vicente Calderón, editor of Tijuanapress.com. Thanks for staying with us Vicente, welcome to you Amy.

AMY ISACKSON (Reporter): Thank you.

PENNER: What's the story that you've been covering?

ISACKSON: So this spate of what authorities presume are drug traffickers killing police officers began at 7pm Monday night. There's a different character to these killings in that they are directed at police. The cartel is directly I think challenging the police. First, gunman mowed down a policeman who was just getting off his shift outside a laboratory in southern Tijuana. He was a commercial policeman. And that's where authorities found a note that gunman left that was a threat to the police, saying they will kill five police a week until the chief of public security of Tijuana resigned.  Then, about 40 minutes later, in Rosarito, gunman ambushed another policeman there, it's a little confusing, there was a policewoman eating in a restaurant, gunmen went in, shot up the restaurant, she somehow repelled the attack, the gunmen left, and then they found this other policeman on their way and killed him. Then a half hour later, back in Tijuana, there was a policeman who was at Smart & Final in the parking lot, an auxiliary policeman, and gunman shot and injured him, then Tuesday morning the violence continued and there was a policewoman who was guarding the Red Cross, and the gunmen shot and killed her. And I think that one interesting thing about this is that authorities are saying that gunmen picked these officers off because they're easy targets. Commercial agents are assigned to one building, auxiliary agents don't carry weapons, so they're like sitting ducks. 

PENNER: So Vicente, do we have a sense that this is all the responsibility of one person, one group, what?

VICENTE CALDERON (Editor of Tijuanapress.com):  One particular group led by a guy named Teodoro Simental Garcia, nicknamed "el Teo," which is a lieutenant from the Arrellano Felix drug cartel. He's the one responsible to wage war against the more traditional line of the family of the Arrellano Felix organization last year. Apparently there's a truce among these two factions and the areas east of the cityand south - where Rosarito is - are controlled more or less for them. The authorities have been making a lot of arrests, they've been confiscating a lot of drugs, money, and weapons.  So this is hurting the operation of this organization, and that's why they are trying to change the chief of police, Julian Leyzaola who became the posterboy of an honest cop.

PENNER: Okay, but actually, this goes beyond the chief of police doesn't it? Hasn't the president been cracking down on, talking about President Calderón, cracking down on these drug traffickers?

ISACKSON: The president has made it a cornerstone of his administration since he took office, saying this is what I'm going to do, I'm going to cracking down on drug traffickers and dismantle these large cartels, and it's historic that he's doing it, it's good that he's doing it, however, so far - and I think Tijuana's a little bit of a different case - but so far nationally, there have not been a lot of major changes. I think nationally, according to statistics that I looked at from Reforma and the Transborder Institute, killings are about on par with last year, there has not really been an appreciable drop, and also 215 police have been killed nationally, according to these statistics, that's compared to 385 of all of last year. So that is also on par as well, and in the U.S. there's no shortage of drugs, there's no sustained price increases.

PENNER:  So are we saying basically that President Calderon's effort has not been very successful?

CALDERON:  I think he has been successful in some aspects, but because he's still bringing the level of impunity down from where he was before, and that's a big important change.  Are they going to be able to diminish the trafficking of drugs in Mexico? I'm not sure, I don't think they are even sure, but this is the result of some level of success, at least in the case of Tijuana, that they are really taking the power away from the drug traffickers and trying to put them back on the institutions.

PENNER: Okay well I thank you very much.